UNCOVERING LIFE CYCLE ENVIRONMENTAL IMPACTS OF NEW PROCESSES ON RESOURCES AND ENERGY RECOVERY OF BAIJIU DISTILLER’S GRAINS

The baijiu industry has witnessed a long-existing challenge for recycling the distillers' grains(DG) to minimize its impact on the environment. A new thermochemical technology is developed for DG disposal by recovering materials and energy, defined as the new technology. This research used materials/energy flow analysis and life cycle assessment to evaluate the environmental impacts of this new technology under different scenarios. The key findings, as compared with the traditional technology are as follows: 1) the new technology, in large part, will contribute remarkable environmental benefits for the whole baijiu production process while considering seven typical life cycle environmental impact categories, and in particular, the global warming impacts will decrease by 40% to 60%. 2) the new technology will bring additional environmental burden in three categories, including 9% in human being toxicity, 26% in marine aquatic ecotoxicity, and 73% in terrestrial biological toxicity. The reason is that the new technology has electricity consumption 19 times that of the traditional technology. The new system has higher impacts in 10 categories when the new technology generates hot water than that generates steam, of which global warming impacts increase by 49%. Based on the assessment result, there are three methods to dramatically decrease the holistic environmental impacts of Baijiu production: 1) producing steam rather than hot water by using recovery thermochemical waste heat in the new DG disposal process; 2) using a natural gas boiler instead of an electric boiler; 3) upgrading the energy-saving facility and energy-intensive processes during scaling up.